Distributor



P. BROWN DISTRIBUTOR Filed June 7. 1926 Dec. 24, 1929.

2 Sheets-Sheet Dec. 24, 1929. P. BRowN DISTRIBUTOR mea June '1. .leze

2 Sheets-Shah 2 INVENTOR. 444, www

W *iq/Z A TTDRNEYS.

Patented Dec. 24, 1929 entre' stares Amm tristi DISTRIBUTOR Application led .Tune 7,

'I This invention relates generally to electrical make and break mechanism and, more particularly, to distributors for use with ignition apparatus of internal combustion engines. f

Theinvention has for an ob]ect the provision, in a mechanism of the general class de scribed, of a novel form of conducting tip for the distributor arm, or other equivalent element, and a novel means for flexibly connecting this tip to a fixed electric terminal adjacent the arm.

The invention has for another object the provision of a distributor of the oscillating arm type which is of generallysimplified and mechanically improved construction, adapting it for quantity production manufacture at low cost and at the same time resulting a better article calculated to give reliable service over a long period of useful life with a minimum of attention. Y

Another object of the invention is to provide means for operating the distributor arm, whether of the oscillating or other type, in a novel manner; characterized in that the arm is engaged with a contact ahead of the interval during which a spark can be produced, in that such engagement is maintained during all of said interval and in that the arm is disengaged from its contact after the end of said interval, whereby all possibility of injury to the contacting surfaces by the destructive effects of the electric spark is eliminated.

f @ther objects and advantages will appear in the following description and will be pointed out in the appended claims.

The invention will be disclosed with reference to the accompanying drawings, in which zf Fig. 1 is a small scale fragmentary View showing a distributor, embodying the invention, and the manner in which it is connected to a magneto;

, Fig. 2 is a small scale view of the distributor taken at right angles to Fig. 1;

Fig. 3 is an enlarged front elevational view of the distributor with its cover removed;

Figs. Ll, 5, 6 and 7 are sectional views taken on the lines 4 4, 5-5, 6-6 and 7-7, respectively of- Fig. 3;

192s. seriar No. 114,212.

Figs. 8, 9, 10 and 11 are conventional views showing successive positions assumed by the distributor arms with relation to their contacts; and

Fig. 12 is an enlarged view of the cam for operating` the distributor arms.

Referring to these drawings, the distributor mechanism is mounted in a suitable case 10, which in this instance is made of insulating material and provided with a removable frontl wall or cover 11, having windows 12, through which the distributing action can be observed. Vllhile case 10 may be suitably supported in any desired way, it is herein shown as secured to a plate 13 suitably secured to one end of the frame A of a magneto M which is, or may be, of the general class disclosed in my copending application Serial No. 62, 057, filed October 12, 1925. In that magneto, two sparks are made during each revolution of thek drive shaft. This drive shaft, indicated in Fig. 3 at 14, extends into the case 10 and carries a gear 15, driving through a gear 16, shaft 17 at half speed. Accordingly, during each revolution of shaft 17, the magneto M produces four sparks. For a four cycle engine, the magneto drive shaft 14 will be connected to turn at engine speer.

The supporting plate 13 carries two studs 18 which pass through opposite side walls of casing 10 and through cover 11 and the cover is clamped to the casing and the casing clamped to plate 10 by nuts 19 threaded on the outer ends of these studs. The plate 13 also has fixed thereto three somewhat shorter studs, which extend into the interior of casing 10 and terminate short of cover 11. One of these last named studs, designated 20, is located centrally between the side walls of casing 10 and near the lower part thereof. The other two, designated 21, are arranged on opposite sides of stud 2O and somewhat below the latter. All of the studs 20 and 21 are made hollow and grooved as shown to receive lubricating wicks (not shown). The stud 2O serves to support the shaft 17 which is of tubular form for that purpose. The studs 21 each support a hollow shaft 22 which carries an oscillating distributing arm 23, herein shown as made of insulating material.

The lower end of each arm 23 is disposed between a disc 24 and a cam follower 25, these three parts being held together by a rivet 26. The assembled parts 23, 24 and 25 are forced onto shaft 22 and held thereto by drive fit. The two earn followers 25 both ride on a single cam 27 which is secured, as by a rivet 28 to the gear 16, above described. Each follower 25 is urged toward the cam by a torsional spring 29, the coils of which encompass the disc 24 and the ends of which bear one against the distributor arm 23 and one against the adjacent side wall of casing 10.

The distributor arms 23 extend upwardly, one on each side of central baille plates 30 and 3l which are formed as a part of casing lO, and terminate near the upper wall of the latter. The upper end of each arm 23 plays between and is adapted alternately to engage a pair of contacts. These contacts are designated generally as c1, c3, c2, ct, and the contacts c1 and c3 are alternately engaged by the left hand arm 23 (Fig, while the contacts c2 and c4' are alternately engaged by the right hand arm The baille 30 depends from the top wall of casing 10 between the contacts 03 and c2 as a protective measure, since these two cont-acts are relatively closely spaced. Formed as a part of the upper wall of casing l0 and extending upwardly therefrom are a series of four sockets 32, one for each of the contacts just described. Each socket is located generally above a contact and has therein a part which is electrically connected to that contact. The sockets are adapted to receive the heavily insulated parts t of spark plug wires The several contacts, just described, are identical in construction and they are each connected to the spark plug wire w in a similar manner. A description of one Contact and :its connection to a wire w will thus suf- `lice for all. Referring to Fig. 6, a connecting strap 34, made up from a relatively 'thin strip of metal, such as brass, and bent into right angular form, is embedded in the case l0 during the operation of forming the same. One face of one leg of strap 34 lies substantially flush, or preferably just slightly below, the inner face of the back wall of casing l0, while the other leg is embedded in the top wall and has its free end projecting into the base of socket 32. Holes are punched out of the strap and screw threaded. One such hole 36 is formed in the upper leg of strap 34 and in axial alinement with socket 32. A screw threaded tip 37 is secured to the lower end of wire w and this tip is threaded into hole 36, whereby wire w is securely connected to strap 34. The other hole, designated 38, is formed in the lower part of the other leg of strap 34 and serves to support a spool which carries a coil spring 3S) forming the active part of contact c2. rf'his spool, as shown, is a composite one but it need not necessarily be so constructed. As shown, it is made up of two pairs of washers separated and axially spaced by an intervening sleeve 40. The washers 4l and 42 of each pair are of difierent diameter and disposed in contiguous relation,-the smaller washers 42 being engaged by the ends of sleeve 40. A screw 43 passes through the several washers and sleeve 40 and is threaded into the hole 38 of strap 34. The washers 4l are slightly larger in outside diameter than the spring 39 and are engaged by the ends of the latter, while the washers 42 are of a size to lit wit-hin the convolutions of spring 39, forming the shoulders of a spool, which shoulders hold the ends of a spring 39 in centralized relation with respect to the axis of screw 43 and at the same time leave the central portion of the spring free to be flexed toward the screw, if and when necessary, as arm 23 moves into engagement therewith.

The terminal of the magneto usually consists of a metallic button 44. Extending through the supporting plate 13 is the circular flanged end 45 of a bushing 46, the latter extending through the back wall of casing l0 and projecting toward but terminating short of cover 11. A screw threaded stud 47 eX- tends through bushing 46 and is held thereto by nuts 48 and 49 disposed near opposite ends of the stud. The rear end of stud 47 projects beyond nut 49 and toward magneto contact 44. Said end carries a coil spring 50, the coils of which are engaged with the threads of stud 47. The free end of spring 50 presses against the magneto contact 44 to electrically connect the same to the stud 47. The spring also serves to press the flange 45 of bushing 46 against the outer face of the back wall of casing 10. Inside the casing, the stud 47 is electrically connected to a pair of conducting arms 52 which are clamped together and against the inner end of bushing 46 by nut 48. These arms are disposed in horizontal relation and just above the baille 31, heretofore described, which baille engages the lower edges of arms 52 and prevents them from turning. The arms 52 project in opposite directions from stud 47 and terminate near the central portions of arms 23 and in front of the same. Each free end of each arm 52 is bent in substantially semi-circular form, as

at 53. rfhe portion 53 of one arm 52 is re-' versely disposed to the corresponding portion of the other arm so that the two portions cooperate to form a complete embrasure for a cylindrical conductor, to be described.

Each distributor arm 23, which, as above described, is constructed of insulating material, has a novel form of conducting tip and a novel flexible electrical connection to the arms 52. The tip and connection are extremely simple in construction, inexpensive to manufacture, and capable of being easily and quickly assembled. These two parts are Gil made from a suitable length of acommon, close-wound coil spring. Havinga spring of suitable length, the same is grasped at two closely adjacent pointsV and pulled in opposite directions tostretch out the intervening convolution, or convolutions, as the case may be, thus forming two coil spring sections 55 J the tip, a hole 58 is provided in arm 25 and,

after section 55 has been slipped over the tip of arm 23, the section 56 is passed through hole 58 from the back of the arm so that the connecting wire 57 engages the back of arm 28 and thus prevents the adjacent end of spring section 56 from being pulled out of hole 58. The other endof section 56, which projects forwardly from arm 26 is then bent.

downwardly and slipped between the embracing portions 53 of arms 52, whereby such end is anchored and at the same time electrically connected to the magneto terminal.. The section 56 is of ample length to permit free oscillation of arm 23 through the desired angular limits.` j

It will be obvious that the conducting tip and flexible connection are desirable from the point of view of low manufacturing cost, not only in so far as the cost of the material is concerned but also and more particularly in so far as the cost of forming the material and assembling the parts thus formed. The

y spring can be formed from standard stock in an instant and assembled on the arm very quickly and conveniently even by unskilled operatives. At the same time a conducting tip is formed for thearm which does not add materially to the bulk of the latter nor de tract from its appearance. Also, the arm 23 is not weakened, as it would be if it were drilled through at the narrow tip to receive the rivets which would be necessary to hold a conducting plate in place on the arm. The tip of the arm can be made small and of neat .appearance in contrast to similar arms of the prior art which have conducting plates rive eted thereto. It is a difficult .and time consuming task to properly secure a conducting plate to an arm of bakelite or similar material and much labor is saved by the present improvement. Also the Vdescribed arrangement is adequate for its purpose and reliable in operation. A positive connection between the tip is formed by a flexible connection which is formed as an integral part of the conducting tip. f y

The above described feature of the invention is obviously independent ofthe various details disclosed relating to the casing, contacts, driving mechanism and so forth. It is equally useful, whether one or more oscillating distributor arms are used. f

While, according to the above feature of invention, the mechanism for oscillating the distributor arms may be of any suitable type, the invention according to other features, is characterized by a novel plan of operating these arms. The primary purposes of the novel plan of operation to move the distributor arm into engagement with a contact before an electroinotive force is, or can be, generated by the magneto under any normal conditions; to hold the parts in contact under pressure over an interval atleast equal to the entire range of the spark advance mechanism; and i'inally .o disengage the parts after all possibility of the generation of anelectromotive force has passed. lnthis way, no spark can occur between a contact and the conducti ing tip of the dist'ributorr arml and the con- Vtactino' )arts are thereb orotected against the destructive effects of the electric spark.

To accomplish the purposes just described, the cam 27 is constructed as shown in Fig. l2. It has four dwell portions, viz, a low dwell portion 66, a high dwell portion 6l and two intermediate dwell portions 62, spaced ninety degrees apart and each. of relatively great angular extent (as shown more than l5 degrees). Connecting the dwell portion 66 to the left hand dwell portion 62 is a rise portion 63 and connecting such portion 62 to the dwell portion 6l is a second rise portion 64. The dwell portion 6l is connected to the right hand dwell portion 62 by a drop portion 65 and said portion 62 is connected to* dwell portion 60 by a second drop portion 66. The difference in radii between the dwell portions 60 and 61 is sufficient to cause each arm 23 to be moved from one of its contacts to the other while the difference between the radii of dwell portions 60 and 62 or 6l and 62 is suicient to cause each arm to be moved from one ofits contacts part way toward the other and into an intermediate position.

Each arm 23 will, during each revolution of cam 27 have four dwell positions and these four positions are illustrated in successive order in Figs. 8, 9, l0 and 1l. Starting with the parts positioned as in Fig. 8, and assuming that cam 27 is turning in the direction of the arrow, the left hand arm 23 has just engaged contact c3 while the right hand arm 23 has just completed niovement from contact cAk toward the left into an intermediate position. As cam 27 turns, the two arms will dwellin the illustrated positions for a substantial interval. As shown, this dwell interval is over 45 degrees which is relatively very large when one considers that spark is produced by magneto M once during each `9() degree movement of cam 27.

As the cam continues to turn, both arms, having` reached the ends of their dwell intervals, move very rapidly to the left, whereby the left hand arm 23 is first moved out ot engagement with contact c3 and the right hand arm is subsequently moved into engagement with contact c2, as shown in F ig. 9. The arms then dwell in these positions for another relatively large interval, after which the right hand arm 23 moves to the right out ot engagement. with contact e2, While the lett hand arm moves to the left into engagement with contact c2. The parts are then positioned as in Fig. 10 and dwell in the positions there shown for another substantial interval. At the end o'lf the latter cam 27 causes the left hand arm 23 to move quickly to the right out of engagement with contact c1 and the right hand arm to move quickly to the right into engagement with contact ct'. The parts then occupy the relative positions shown in F 11 and dwell in these positions for a substantial interval. At the end ott the latter, the cam 27 quickly moves the right hand arm 23 to the leftout of engagement with contact c4 and moves the left hand arm 23 quickly to the right into engagement with contact c3.

In F ig. 12 there are indicated angles s between dotted lines 67, and these angles represent conventionally the range o1l the spark advance mechanism of the magneto M. The boundary lines 67 of each angle s indicate the earliest and the latest tii'nes at which a spark can be produced. Comparing the boundary lines 67 ot angles s with the boundary lines of the angles of the dwell portions and 61. It will be apparent that each contact is engaged by its arm before there is any possibility oi a spark being produced by the magneto and that this contact is not broken until after all possibility ol a spark being produced has passed.

Aside from the feature just mentioned, it is to be noted that the arms move very rapidly into and out ot contact for the rise portions 63 and 64: and the drop portions 65 and 66 are very steep and oi' relatively small angular extent in comparison with the dwell portions. Also, it should be noted that each arn'i 23 not only moves so as to engage its cylindrical conducting tip 55 with contact spring 39 but moves enough fartl er so that the spring 39 is flexed. The Contact between two cylindrical surfaces whose axes are disposed at right angles would be point contact but point contact is avoided here by moving` the arm far enough to iiex t-he spring 39 ant make it encompass a substantial are oi the cylindrical suriace of tip 55. The latter makes a seat for itself in the yielding contact spring 39, and thus an adequate area of engagement between the contacting parts is created.

The invention provides a distributor which is not only relatively simple in construction and inexpensive to manufacture but which l in action and calculated Ylor is also reliable lone* use'lul lite in service. The manner of operating the distributor arms to avoid sparking between the conducting tips thereor' and t-he contacts insures long lit'e due to the elimination of the destructive eil'ects of the electric spark. Also, while provision is made 'for adequate contact between the disi tributor arms and the contacts, these parts are never subjected to any material strain. There are no impacts between the engaging parts nor any material rubbing action therebetween, which would tend to cause rapid wear. Accordingly, the distributor is capable of long useful life in service without requiring attention or necessitating adjustments or repairs.

rllhe features relating to the construction and mounting ot the contacts c1, c2, c3 and c'Al and the anchoringY connection for the ilexible conductor 5G were invented by Terrence G. Louis of Springfield, Massachusetts, prior to the tiling of this application. Such features constitute the subject matter ot an application No. 114,178 filed in his name on June 1.7, 1926.

The iiivention has been disclosed herein, in an embodiment at present preferred, for illustrative purposes, but the scope ot' the invention is delined by the appended claims rather than by the foregoing description.

Vhat I claim is:

1. In a device of the class described, a plurality of contacts, a suitable support for the saine, an arm mounted for oscillating movement and movable to successively en gage said contacts in proper sequence, a Fixed electric terminal adjacent said arm, and a coil spring connected at one end to said terminal and having a portion near its other end mounted on said arm to form a conducting tip therefor, the remaining portion of said spring forming a flexible connection between said tip and terminal.

2. In a device of the class described, a plurality ot contacts, a suitable support for the same, an arm mounted for' oscillating movement and nfiovahe to successively engage said contacts in proper sequence, a fixed electric terminal adjacent said arm, and a coil spring connected at one end to said terminal and having a portion near its other end slipped over and encompassing the free end of said arm to form a conducting tip therefor, the remaining portion oit' said spring forming a flexible connection between said tip and terminal.

3. In a device of the class described, a plurality of contacts, a suitable support for the same, an arm mounted for oscillating movement and adapted to successively engage said contacts in proper sequence, the free end of said arm being of insulating material and having an opening therethrough located between the tip o'f the arm and its axis of oscillation, a fixed electric terminal adjacent the arm, and a coil spring one section of which is slipped over the tip of said arm to form a substantially cylindrical conducting tip therefor and the other section of which is passed through said opening and connected to said terminal, said last named section forming a flexible conductor between the terminal and tip with suiiieient slack to permit oscillation of said arm over the desired range.

4. A distributor, Comprising, two pairs of contacts, an oscillating arm for each pair of contacts adapted for alternate engagement therewith, and operating means `for said arms constructed to intermittently move each so that it moves from a position intermediate the contacts, into and out of positions whereinit engages first one and then the other of its Contacts and remains stationary for an interval in said intermediate position and also in each of said engaging positions, said operating means arranged to hold one arm stationary in its intermediate position while the other arm is held stationaryT in engagement with either of its contacts. y

In testimony whereof I have aiiixed my signature.

PHELPS BROWN. 

